Yes, sure. Any such new cooperative wouldn’t automatically come with the colleagues or contract/revenue which his former employer had just handed off to the newly formed business discussed in the blog post, and its creation wouldn’t solve the feelings of hurt or betrayal which the post describes after he was excluded from certain discussions and interpersonally cut off by people he had considered friends.

But certainly no business, whether cooperative or fully capitalist, has exclusivity on participating in KDE, nor has he been banned from the community. This is more about him feeling ostracized and unwelcome than formally forbidden, and also about him being surprised that his priorities around the structure and ownership of the new business weren’t shared by his colleagues.